hw/misc/allwinner-sramc.c

   1 /*
   2  * Allwinner R40 SRAM controller emulation
   3  *
   4  * Copyright (C) 2023 qianfan Zhao <qianfanguijin@163.com>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "qemu/units.h"
  22 #include "hw/sysbus.h"
  23 #include "migration/vmstate.h"
  24 #include "qemu/log.h"
  25 #include "qemu/module.h"
  26 #include "qapi/error.h"
  27 #include "hw/qdev-properties.h"
  28 #include "hw/qdev-properties-system.h"
  29 #include "hw/misc/allwinner-sramc.h"
  30 #include "trace.h"
  31
  32 /*
  33  * register offsets
  34  * https://linux-sunxi.org/SRAM_Controller_Register_Guide
  35  */
  36 enum {
  37     REG_SRAM_CTL1_CFG               = 0x04, /* SRAM Control register 1 */
  38     REG_SRAM_VER                    = 0x24, /* SRAM Version register */
  39     REG_SRAM_R40_SOFT_ENTRY_REG0    = 0xbc,
  40 };
  41
  42 /* REG_SRAMC_VERSION bit defines */
  43 #define SRAM_VER_READ_ENABLE            (1 << 15)
  44 #define SRAM_VER_VERSION_SHIFT          16
  45 #define SRAM_VERSION_SUN8I_R40          0x1701
  46
  47 static uint64_t allwinner_sramc_read(void *opaque, hwaddr offset,
  48                                      unsigned size)
  49 {
  50     AwSRAMCState *s = AW_SRAMC(opaque);
  51     AwSRAMCClass *sc = AW_SRAMC_GET_CLASS(s);
  52     uint64_t val = 0;
  53
  54     switch (offset) {
  55     case REG_SRAM_CTL1_CFG:
  56         val = s->sram_ctl1;
  57         break;
  58     case REG_SRAM_VER:
  59         /* bit15: lock bit, set this bit before reading this register */
  60         if (s->sram_ver & SRAM_VER_READ_ENABLE) {
  61             val = SRAM_VER_READ_ENABLE |
  62                     (sc->sram_version_code << SRAM_VER_VERSION_SHIFT);
  63         }
  64         break;
  65     case REG_SRAM_R40_SOFT_ENTRY_REG0:
  66         val = s->sram_soft_entry_reg0;
  67         break;
  68     default:
  69         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
  70                       __func__, (uint32_t)offset);
  71         return 0;
  72     }
  73
  74     trace_allwinner_sramc_read(offset, val);
  75
  76     return val;
  77 }
  78
  79 static void allwinner_sramc_write(void *opaque, hwaddr offset,
  80                                   uint64_t val, unsigned size)
  81 {
  82     AwSRAMCState *s = AW_SRAMC(opaque);
  83
  84     trace_allwinner_sramc_write(offset, val);
  85
  86     switch (offset) {
  87     case REG_SRAM_CTL1_CFG:
  88         s->sram_ctl1 = val;
  89         break;
  90     case REG_SRAM_VER:
  91         /* Only the READ_ENABLE bit is writeable */
  92         s->sram_ver = val & SRAM_VER_READ_ENABLE;
  93         break;
  94     case REG_SRAM_R40_SOFT_ENTRY_REG0:
  95         s->sram_soft_entry_reg0 = val;
  96         break;
  97     default:
  98         qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
  99                       __func__, (uint32_t)offset);
 100         break;
 101     }
 102 }
 103
 104 static const MemoryRegionOps allwinner_sramc_ops = {
 105     .read = allwinner_sramc_read,
 106     .write = allwinner_sramc_write,
 107     .endianness = DEVICE_NATIVE_ENDIAN,
 108     .valid = {
 109         .min_access_size = 4,
 110         .max_access_size = 4,
 111     },
 112     .impl.min_access_size = 4,
 113 };
 114
 115 static const VMStateDescription allwinner_sramc_vmstate = {
 116     .name = "allwinner-sramc",
 117     .version_id = 1,
 118     .minimum_version_id = 1,
 119     .fields = (VMStateField[]) {
 120         VMSTATE_UINT32(sram_ver, AwSRAMCState),
 121         VMSTATE_UINT32(sram_soft_entry_reg0, AwSRAMCState),
 122         VMSTATE_END_OF_LIST()
 123     }
 124 };
 125
 126 static void allwinner_sramc_reset(DeviceState *dev)
 127 {
 128     AwSRAMCState *s = AW_SRAMC(dev);
 129     AwSRAMCClass *sc = AW_SRAMC_GET_CLASS(s);
 130
 131     switch (sc->sram_version_code) {
 132     case SRAM_VERSION_SUN8I_R40:
 133         s->sram_ctl1 = 0x1300;
 134         break;
 135     }
 136 }
 137
 138 static void allwinner_sramc_class_init(ObjectClass *klass, void *data)
 139 {
 140     DeviceClass *dc = DEVICE_CLASS(klass);
 141
 142     dc->reset = allwinner_sramc_reset;
 143     dc->vmsd = &allwinner_sramc_vmstate;
 144 }
 145
 146 static void allwinner_sramc_init(Object *obj)
 147 {
 148     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 149     AwSRAMCState *s = AW_SRAMC(obj);
 150
 151     /* Memory mapping */
 152     memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_sramc_ops, s,
 153                            TYPE_AW_SRAMC, 1 * KiB);
 154     sysbus_init_mmio(sbd, &s->iomem);
 155 }
 156
 157 static const TypeInfo allwinner_sramc_info = {
 158     .name          = TYPE_AW_SRAMC,
 159     .parent        = TYPE_SYS_BUS_DEVICE,
 160     .instance_init = allwinner_sramc_init,
 161     .instance_size = sizeof(AwSRAMCState),
 162     .class_size    = sizeof(AwSRAMCClass),
 163     .class_init    = allwinner_sramc_class_init,
 164 };
 165
 166 static void allwinner_r40_sramc_class_init(ObjectClass *klass, void *data)
 167 {
 168     AwSRAMCClass *sc = AW_SRAMC_CLASS(klass);
 169
 170     sc->sram_version_code = SRAM_VERSION_SUN8I_R40;
 171 }
 172
 173 static const TypeInfo allwinner_r40_sramc_info = {
 174     .name          = TYPE_AW_SRAMC_SUN8I_R40,
 175     .parent        = TYPE_AW_SRAMC,
 176     .class_init    = allwinner_r40_sramc_class_init,
 177 };
 178
 179 static void allwinner_sramc_register(void)
 180 {
 181     type_register_static(&allwinner_sramc_info);
 182     type_register_static(&allwinner_r40_sramc_info);
 183 }
 184
 185 type_init(allwinner_sramc_register)